1. Field of the Invention
This invention relates to a changeable letter sign system for normally overhead, illuminated readerboards, the system including a plurality of panels, each bearing on the front face thereof a letter: number or punctuation character: the panels being combinable to collectively present a message displayed on the readerboard, there being means for retaining the panels with respect to the front wall of the readerboard, each of the panels having magnetically attractive material thereon whereby the individual panels may be positioned and removed by a suitable tool, carrying a magnet. The magnetically attractive material is preferably in the form of a strip positioned on the front face of the letterbearing panel and in contiguous relationship with the peripheral inner and outer edges of the letter, character or number on the panel whereby the magnet, carried by a handle on the end of an extension pole may be brought into engagement with the strip of magnetically attractive material to permit changing of the panels on the readerboard.
2. Description of the Prior Art
Readerboards are normally illuminated signs which are displayed in conjunction with a business enterprise to advertise a feature or function of the business and may be positioned in elevated positions such as for instance on a sign support. It has been known to provide readerboards with transparent walls whereby interior lights may shine therethrough to illuminate letters which are carried on one or both of the transparent, back lit walls of the readerboard.
It has also been known to provide such readerboards and particularly the faces thereof with means for retaining panels which are generally rectangular in plan configuration and of varying widths for self spacing and which panels have a letter, number or other character thereon which is to be displayed on the readerboard, the combination of such panels delivering a message to the viewer of the readerboard.
Such retaining means have taken the form of tracks on the wall of the readerboard which include a pair of spaced apart rails, the rails receiving therein opposed edges of the letter-bearing panel whereby the panel may be inserted in the track either by moving the panel longitudinally of the track for purposes of insertion and placement or by placing one edge of the panel beneath one rail and then swinging the panel to a position where the opposed edge is behind the other rail, resulting in the retention of the panel by the track with respect to the wall of the readerboard.
Normally the panels have been placed with respect to the retaining means either manually or through use of a suction cup used to grasp and position the panel with respect to the wall of the readerboard. Yet further, it has been known to provide the panels with magnets thereon whereby such magnets may be attracted to magnetically attractive material which is formed as a part of the readerboard to thereby retain the panel on the readerboard.
The structure and systems described above are functionally satisfactory, except in the case of three dimensional letters which are carried on a panel, the panels carrying three dimensional letters being difficult to place, particularly on readerboards which are high overhead such as, for instance, on a tall sign support.